Many observational studies have suggested that vitamin D may have benefits for heart health. Now a randomised trial has found that vitamin D appears to reduce levels of LDL, or “bad” cholesterol. Researchers randomly assigned 576 post-menopausal women to either a daily dose of 400 units of vitamin D and 1,000 milligrams of calcium, or a placebo. They followed them for three years.

By the end of the study, published in Menopause, the vitamin D group had significantly higher serum levels of vitamin D, and a small but notable drop in LDL.

“We don’t have enough here to say that we’ve figured it all out,” said the lead author, Dr Peter F Schnatz, a professor of internal medicine at Jefferson Medical College in Philadelphia.

The change in LDL, he said, “is significant, and in the right direction, but maybe not enough to say that we’re going to prevent people from getting heart disease.”